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Laser Shoots Down Artillery Shell In Flight
An anonymous reader writes "The Mobile Tactical High Energy Laser is a joint project between the US Army and the Israeli Defense Ministry, with much of the work being done by TRW. Tuesday they had a spectacular success when they shot an artillery shell out of the air."
... when they fire one of these at a disco ball? heh.
Reading through the article doesn't give much info about details such as:
How much does one unit cost?
How long is the "reload"/"re-aiming" time?
Will it survive real heavy artillery battle?
They say in the article that it was developed by the army and TRW, but we all know it was Mitch Taylor and Chris Knight.
like the ones used to pass the first generation patriot missle system. The gen 1 patriots were so bad that final analysis showed that in one test the patriot missed the mark only to have the target slam into it, thus causing both to break up. In the official scoring this was marked as a hit and win for the patriot sytem even though it was a random fluke. Unless someone not affiliated with the military or the defense contractor verifies the results I shall remain skepticle until field use proves the system.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
No, that was James Bond.
Fascism starts when the efficiency of the government becomes more important than the rights of the people.
Lasers to knock out 'metal things' have been around for decades as well. The difficult part has been tracking very high speed objects from a distance.
There was a big Navy project to put a laser on a ship. I have no idea if that was ever put into operation.
There was the 'Star Wars' Alpha program that was run during the Regean military buildup. And King George the Second appears to be trying to breath life back into the project.
What makes this news item 'interesting' is that the DoD seldom comments on successes like this unless program funding is at stake or some politico needs to be impressed.
Regards.
Where does the laser go if they miss the shell? Disperse into a cloud? Hit a passing 747?
Somehow, I doubt a 747 would be flying into a live fire area (Iraqi airliners excepted). Many current artillery shells have high trajectories that go several km in altitude. As a matter of fact, I once worked on a system that had an operator warning "NOTIFY NASA", for when a shell trajectory was computed to go above a certain altitude.
Fascism starts when the efficiency of the government becomes more important than the rights of the people.
"Didn't they have this back in the 60's? correct me if I'm wrong, I was always told this. "
Well, the technnology was developed recently, but yeah it did exist in the 60's. I think it was called the Alan Parsens Project.
"Derp de derp."
A cloud of shell parts has a very different aerodynamic profile. The remnants of the shell might still be initially traveling in the same direction, but the fragments will not maintain that course. You only have to change the trajectory of the shell enough to make it fall short of its target.
Outside of a dog, a book is a man's best friend. Inside a dog, its too dark to read.
hehe, you just pointed out one of the biggest benifits of this type of antiprojectile system. If they work and are fast enough you can explode the ordinance over the enemies own lines. If the enemy is using nasty stuff like biological, chemical, or nuclear arms you've just doubled the effectiveness of your defense by making it an offense.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
All I asked for is that the word "la-ser" be printed with quote marks around it, is that so hard?
You see? You see? Your stupid minds! Stupid! Stupid!
Linux user since early January 1992.
As it begins it's decent, itmay speed up with gravity, or slow down even more, depending on the air-resistence.
It's still going to closely approximate an ideal paraboloid, except at the terminal stage of flight where it's going to travel more vertically than ideal equations predict. In addition, the shell travels way up high, easily visible to radar, where most missiles people on the surface worry about tend to lose themselves in ground clutter, SR/IR/ICBMs aside.
Second, a shell goes much faster than a rocket.
No, not really, especially during the terminal stage when the shell's maximum speed is limited by terminal velocity; a shell gets one big push at the start of its flight, and is purely passive afterwards (well, excepting rocket-assist and basebleed, but still). A rocket continues to accelerate as long as the motor burns, and can reach speeds far in excess of artillery shells, which can routinely be seen with the naked eye as they hurtle downrange. The trouble here is that "rocket" spans such a wide range; a rocket can be a nice slow fat subsonic target like a Silkworm, or a Mach 2.5+ evasive-action-capable SS-N-22. HARM missiles have a top speed of 2300kph, ferinstance, a good bit faster than terminal velocity of most things that only travel ballistically.
But in either case, shooting down a shell in flight is really nothing new. The Brits had Sea Dart back in the Falklands, and that was capable of shooting down 4.7" artillery shells. Shooting down the shell is *not* new, or exciting or innovative. Doing it with a laser is.
That's why they're called TESTS. This is like complaining to the Wright Brothers, "That's nice but it's not as hard as carrying 50 people across the Atlantic non-stop." It's all hard, of course, so one has to expect little steps like these.
I live ze unknown. I love ze unknown. I am ze unknown.
As an ex army cannoneer, I'd like to know more about the artillery shell that was destroyed by the laser.
...
... we used radar at night to track where our shells were landing.
Here's what I can tell you
I worked on the m198 Howitzer, which can fire a 100 pound 155mm HE (high explosive) shell at a muzzle velocity of around 750m/s. With other combinations of propellants and rounds, the velocity could easily reach 1 kilometer per second or greater. Not too shabby for a 100+ pound piece of steel going down range into a target the size of a 5 gallon bucket.
The inherent problem with an artillery shell is that its trajectory is highly predictable... its all about math. So, for the purposes of a high powered laser, as long as it can perform some really nifty calculations in a split second, and point itself right into the path of a traveling artillery shell, then the shell will actually fly into the laser if everything goes according to plan.
Artillery shells can also be detected with radar
So, whats next... assuming that the laser works by calculating the trajectory of the shell, and positions itself ahead of the shell, would the next advancement in artillery be shells that wobble to avoid running into a high powered laser?
Besides these basic artillery shells, there are also laser guided and rocket assisted shells, whos trajectories may be a bit harder to calculate.
Here are just some of the factors that go into calculating the trajectory of an artillery shell...
1. The exact weight of the shell.
2. The type, amount, and temperature of the propellent.
3. Resistence of travel (air friction) based on weather conditions and altitude.
4. Curvature of the earth and gravity.
So there you have it folks... this laser is an amazing piece of technology.
Skiers and Riders -- http://www.snowjournal.com
This wasn't rigged. Everyone was told ahead of time that the target missle had a GPS receiver on the warhead as well as a C-band beacon.
The purpose of the test was not in acquisition and tracking, but in the kill vehicle technology (plot a path to a moving point, get within infrared range, correct course, and detonate). Sounds simple, but it gets a bit trickey a closing speeds of ~10km/s.
The x-band satellites just weren't operational over the pacific when these tests were being done. So, when Colo springs control asked Hawaii where the missle was, it responded with information from the GPS receiver but provided artifically 'degraded' data stream. This was underlined and not hidden in the test plan (released before the test). It was done as a 'simulation' of x-band (national missle defense system) data.
Honestly, peoples hostility to this program in current time has me baffled.
The reson pundits of ABM tech would underscore every little failure, or break out conspiracies and wave around "rigged" results, was that we should not be researching ABM technology. Russia's on board now, you can stop pissing your pants worrying were going to invoke a nuclear war by having this technology.
If you hate being lied to, you should take the time to better research what people (including myself) and news sources in general tell you.
-malakai
-Malakai
A Dragon Lives in my Garage
ARGHHHHHH. This question gets asked every time a new "laser shoots something that flies out of the air" story appears on slashdot. (Strangely enough these stories are quite regular.)
The answer I've seen most often is that even the best mirrors don't reflect 100% light, and any laser light that gets "through" will quickly degrade the mirror from the inside out, allowing even more light through.
But for even more info... try a slashdot search for laser stories, and then search the comments for the word "mirror."
"And like that
Nope. This isn't _Star Trek_...
(1) To feed people, first you need to wipe out the bastards using food as a weapon -- a real problem in many conflict zones. Mogadishu, anyone? Recall what happened when the lightly-armed UN handed out food? It got seized by the militias. In other places, it'd be the government that'd confiscate the food.
(2) Your peace is not their peace. Radical Islamists want the world to be Moslem. Some others would prefer there to be NO Moslems. Some prefer equality of opportunity, while others prefer equality of poverty. Some want a modern world, while others will only be happy with a Year Zero Khmer Rouge-style approach. You can't make them all happy, simultaneously.
At any given point in history, probably a large portion of the human population is Thoroughly Pissed Off. Are you going to tell them to just completely change their value systems and surrender?
Only the dead have seen the end of war.
They make it sound as if an artillary shell is a HARDER taregt to hit than a rocket. Rockets accelerate, tumble, and move erratically. Artillery shells move in well understood, computable trajectories. They probably had the damn flight path of the shell computed before they fired it. It's one thing to shoot down a shell when you know it's path ahead of time, another entirely to get a fix on an unknown, erratic rocket and destroy it.
You are right that it is easy to compute the trajectory of an artillery shell if you know the speed (and this you can measure by radar). You just solve the same equations that the artillery battery did before firing. These computations are very well understood. That being said, I disagree with the statement that (cruise) missiles are easier.
First of all, rockets don't really "accelerate, tumble, and move erratically" that much. They can be mostly considered like an artillery shell with a constant forward force. A cruise missle may make one or two smooth turns during its flight, rocket artillery not a single one. If you are firing a laser it is a safe bet that the missile will keep on the same path for a couple of more seconds - and remeber, the laser reaches its target instantaniously so it is easy to cancel or readjust your beam.
Now a couple of factors that makes it harder to kill the artillery shell
-It is much faster than a (cruise) missile -It is smaller, about one third of the size -It is not particullary sensitive. The shell is basically a piece of metal shaped like a cone travelling only by momentum; the cruise missile has little wings, complex control systems and yes, it burns rocket fuel.
I think this is quite revolutionary. I venture guess they will put these bastards on Aircraft carriers. Not a hostile shell, missile, airplane or UAV will come within miles. And there are nuclear power plants to drive them.
Tor (served in the Swedish artillery)
There was some confusion as to what value there was in shooting a hole in an artillery shell.
If you hit a rocket with a laser, your best shot would disable its guidance and control systems. This would quite possibly shut down its engine, but would certainly prevent it from hitting you at all. Secondary targets on a misile include control surfaces, engine, and fuel, all of which have the potential to destroy the misile before it reaches you.
Now if you are applying these countermeasures on a misile that is already very near you, another factor comes into play... what kind of a hit it is. If you're on an aircraft carrier and someone shoots an antiship misile at you from reasonably close range, and it's of a Russian design, it's going to fly up at 45deg, and then sharp down at 45 degrees at you, very fast. If you manage to detonate the propellant or disable the rocket, there's still a good chance it will hit you and deliver its full damage. (a "hard" hit) If you get luckier and detonate its payload, or destroy the control and detonation systems, you are still going to get hit, but this is a "soft" hit. The misile body, rocket motor, and all the other bits (in one piece or many) will still do appreciable damage, but at least it's not likely to sink the boat.
Shells are different. Major shells are going to have armor piercing or high explosive payloads, and C4 just doesn't blow up if you vaporize it with a laser... it burns. So you are not all that likely to detonate it. Shells are fired with great precision, and if all factors are known, they will land with that same precision. Your best hit on a shell is to damage it physically, and change its aerodynamic characteristics. Take a shell and scar the nose with a pocket knife, and it's totalled... you won't hit anything with it, it's not going to fly straight anymore. The laser just has to damage the casing. It's worth noting that if you punch a hole in it fast enough and start burning up the C4 inside, you might just plain burst the shell by simple gas expansion. In any event, it's effectively dealt with. It may still land and blow up, but it's not going to hit what it was aimed at.
Even changing the orientation of the misile/shell is very useful in countermeasures. Most of these have "shaped charges", where the explosive payload is directed in a very carefully engineered way to do maximum damage. When hitting a tank with an antitank round, having the "business end" hit the tank is the difference between destroying the tank (piercing the armor and sending chaff all around the cabin to kill the crew) or doing negligible damage by exploding harmlessly outside the tank. Misiles are essentially the same... a misile that would normally destroy a target may not even detonate if it's tumbling when it hits and contacts sideways, and if the target is even lightly armored, damage will be minimal rather than fatal.
I expect lasers to prove very effective as a projectile countermeasure.
I did have one curiosity about the shell test they did... does anyone know how long they "beamed" the shell before it was effectively dealt with? That's one thing that must be considered... if you have to hold the beam on the target for a considerable length of time, it may be much more difficult to get in a fatal shot. Misiles tend not to roll, so if you are shooting at it from the side, (i.e.you're not the target) you still can hit one spot continuously. Shells on the other hand, are usually designed to spin as they fly downrange, and so targetting the side is actually targetting a band around the shell.
I work for the Department of Redundancy Department.
Anyone who has served on board ship in the US Navy since 1980 knows just how good our targeting systems can be. Ever heard of the acronym CIWS? It stands for Close In Weapons System. It was designed to take out inbound projectiles such as cruise missiles between 10 km and 1 km from the ship. It is still actively deployed on many US ships.
The system consists of a tracking radar system with enough computing power to track up to 150 threats at once. It prioritizes the targeting system based upon inbound speed, size of the object, IFF status, and distance from the ship. Once this sucker is enabled, you'd better hope your planes have their IFF turned on, or they'll be shot down quicker than you can blink.
The system did all this using a Vulcan cannon, which is a gatling gun design throwing depleted uranium rounds downrange. The system was designed to fire and correct inflight to hose down a target until it dropped out of the sky. The system's biggest weakness was the fact that it went through rounds so fast (up to 6,000 rpm theoretical, 2,000 rpm typical) that the magazines had to be HUGE. I once saw a picture of the USS New Jersey after its refit. The 4 magazines on board held enough rounds to fire for a grand total of 15 minutes without stopping. The smaller ships that had the system frequently were limited to less than 2 minutes. A decent laser system's power plant occupying the same space would solve this problem.
This system was successfully demonstrated almost 25 years ago. Its first active deployment was in 1980 or 1981. And you "experts" are trying to tell me that the targeting technology hasn't improved enough since to take down an artillery shell? Oh, please. Go do some very basic research on what's in use TODAY before hollering about weapons tests for stuff that might be deployed tomorrow.
The only question in my mind is the size of the power plant necessary to drive a powerful enough laser to be useful. Can it be mounted on anything smaller than a ship? Anyone know?